Electric welding-machine.



W. E. ANDREWS.

ELECTRIC WELDING MACHINE.

APPLICATION FILED JULY 6, 1914. 1 1 15 461 Patented Oct. 27, 1914.

3 SHEETS-SHEET l.

INVENTIJR.

ATTORNEY W E. ANDREWS. ELECTRIC WELDING MACHINE. APPLICATION FILED JULY 6, 1914.

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ATTDRN EY.

W. E. ANDREWS. ELECTRIC WELDING MACHINE.

' APPLICATION FILED JULY 6, 1914. 1, 1 1 5,46 1. Patented Oct. 27, 1914.

3 SHEETSSHEET 3.

INVENTIJR \Ni'masss'si Mk4)? Y I ATTORNEY i is provided adjusting means for regulating; 80 thtrperiod during which the said circuit reing bracket 17, being fixed upon the upper E. INDB-EWS.

OF BELLAIRK-OHIO, ASSIGITOR OE ON 'E-HALF T0 W. A. STELLERS, OFBELLAIRE, OHIO.

nnnc'rmc WELDING-MAQHINE.

Specification of Letters Patent.

To all whom it may concern: Be it known that 1, WILLIAM E. ANDREWS, a citizenof the United States of America, and resident of 'Bellaire, county of Belmont, and State of Ohio, have invented certain new and useful Improvements in Electric Welding-Machines, of which the following is a specification.

This invention relates broadly to electric welding apparatus, and Specifically to a machine for welding the seamsof tubular sheet metal articles. i

The primary object of the invention is to provide a machine for elect-rlcally welding the meeting or overlapped edges of tubular articles, such, for instance, as coffee pots and other culinary vessels which .are to have an enamel coating applied thereto, which machine is adapted to so firmly and closely weld said edges that the seam is rendered practically imperceptible, especially after the article has been enameled.

A further object is to provide an ap aratus ofv the character mentioned embodylng means whereby the electric circuit supplying the current employed in performing the welding operation is automatically closed and broken at the proper times, and wherein mains closed. e

With these and other objects in view, the invention resides in the features of construction, arrangement of parts and combinations of elements which will hereinafter be fully explained reference being had to the accompanying drawings, forming a part of this specification, in which 'Figure 1 is a top plan view of the invention; Fig. 2 is 'a side elevation of the same,

parts being shown brokenaway; Fig. 3 is a frontend elevationlof the sameg Fig. 4 is a longitudinal section on the lime-4, .Fig. 1; a

Fig. 5 is a transverse section on ,the line 5-5, Fig. 4;; Fig. 6 is a similar sect1on,,on

. the line 66, Fig. 4-; Fig. '7 is' an "enlarged side elevation of the automatic circuit closing and breaking mechanism; Fig.8 is a horizontal section taken on the. line 88,

Fig. 7 and Figs. 9, 10' and l l are'enlarged detail sections taken, respectively, on the lines 9+9, 10-10 and 11 11, Fig. a

Referring to said drawings, n which like designating characters distingu sh like parts throughout the severalv vi'ews1 indlcates generally a suitable supporting frame or table upon which, at one side, is mounted a Patented Oct. 27, 1914. Application filed July 6, 1914. Serial No. 849,026.

pedestal 2 carrying bearings3 in which is journaled one end of a drive-shaft 4. "Said drive-shaft has fixed thereon between said bearings 3 a worm gear 5 with which meshes a gear 6 loosely mounted on a shaft 7 journaled in suitable bearings 8 and 9, the latter provided in an upright member 10 of a .frame' which is generally designated by the numeral 10. A sleeve ll splined on said shaft 7 has its outer end formed to constitute a clutch element, having outwardly dinected teeth 12 which are adapted in. one pos tion of said element to interlock with teeth 13 of a complemental clutch element formed on the hub of said gear 6, thus causing rotation to be communicated from said gear to said shaft. A coil spring 14 interposed between the outer end of the bearing 9 and the ad acent endof said sleeve-ll serves to normally hold the latter in an outwardly thrust position wherein the clutch elements are interlocked. The inner end of said sleeve has formed thereon an annular rib 15 the outer face of which is irregular and constitutes a cam against which rests the upper end of a normally elevated plunger 16, Said plunger is m ovably mounted in avertical positlon w1th1n the tubular portion 1'7 of a supportend of a vertically movablerod 18 whose lower end is pivotally connected to a pedal operated lever 19. A suitabl located retractile sprin 20 normally ho ds said lever in an elevate position, and a spring 21 interposed between the lower end of said plunger and the lower end of the bore in said tubular portion l7 of bracket 17 serves to normall-ymaintain said plunger elevated.

As will be obvious, when the pedal lever is depressed, the .plunger 16 is withdrawn from engagement with the cam face of the rib 15. carried by the sleeve'll, whereupon, actuated by spring 14, said sleeveis immediately shifted into a position. wherein the clutch elements interengage andv the shaft 7 Ebegin's'to rotate. Said cam face is of such form that a complete revolution of the shaft 7 is permitted before the clutch elements are again separated by the action of the plunger, which latter is released by the re.- moval of the foot ressure on the lever. 19 promptly after sai shaft begins to rotate. A short stud '22 is preferably provided on 10 members or" sides of the frame 10 is a bracket 24 of substantially U-shape, in the opposite parallel members of which are journaled' the enpls of a threaded rod or screw25. Mounted on said threaded rod or screw so as'to be rendered adjustable thereon by rotation thereof is a block 26 having fixed therein a wrist-pin 27 which projects through and operates in a slot 28 provided in a rocker-arm 29 intermediate the ends of the latter- Said rocker-arm is pivotally mounted at its lower end, as upon a portion of the frame 10, as shown in Figs. 3, 4 and 5, and has an upper bifurcated end the members of which are disposed in straddling relation to a block 30 which is slidable horizontally within the embrace'of a suitable casing-like guide 31 mounted upon the top of theframe 10. Open longitudinal slots 32 provlded in the members constituting the upper end of the rocker-arm have i received therein the opposite ends of a transversely directed pin33 carried by the block 30, means being thus provided whereby rocking movement ofsaid arm imparts reciprocating movement to said block.

As 1s obvious, by adjustment of the block 26 on the screw 25, the distance of the wristpin27 from the axis of shaft 7 is regulated, thus providing for adjustment of the throw the rocker arm and, consequently, the length of the reciprocating movement of the block 30.

Having one end pivotally connected to the slide-block 30"is a horizontally disposed rod 34 the opposite end of which is connected to a head-block .35 composed of copper or othermaterial highlyconductive of electricity, havinga copper welding wheel, or wheelelectrode, 36- journaled therein. Said head-block is slidably mounted within the embrace of a horizontally disposed guide-member 37 which is vertically movable within a forward extension 31*? of the V S aid block 40 is vertically adjustable guide 31. Vertical pins 74 mounted in the said bracket for adjusting said horn elem trode with respect to said wheel electrode 36, an adjusting screw 42 being suitably mounted for raising and lowering said block, as is clearly shown in Figs. 3 and 4.

An electric transformer, indicated diagrammatically at 43 in Figs. 2 and 4, has its low potential terminals or conductors 44 and 45 connected, respectively, to the headblock 35 andto the bracket 41, the current from said head-block passing directly to the wheel electrode 36, andthe current from the bracket passing to the block 40 and thence to the horn electrode 39.

In practice, the tubular article which is to be' weldedis slipped over the horn electrode 39' and the edges to be welded are properly overlapped, the inner end of the seam being placed directly underneath the wheel electrode 36. When the pedal lever 19 is depressed, causing the rocker-arm 29,1 through the intermediate mechanism, to swing forward, the wheel electrode is thereby actuated to rotate forward and to exert a yielding pressure on the seam interposed 99 between it and the horn electrodeto produce a roper weld, a welding heat being induced y the electric current which passes between the wheel electrode and the horn electrode through the interposed metal. At v the instant that the wheel electrode is actuatd to move forward, as aforesaid, the elec tric circuit which furnishes the heating current is automatically closed. The mechanism by which this is accomplished will now be explained.

Mounted upon one side of the casing-like guide 31 are suitable bearing brackets 46 and 47 which have slidably mounted therein the opposite neck portions of each of two thread- 195 ed shafts 48 and 49. The shaft'48 is threaded outward in opposite directions from a point substantially midway betweenits ends, as shown in Figs. 1, 7 and 8, and has mounted on one of its threaded portions a block 50 119 which is adjustable forward and rearward by rotary motion applied. to said shaft-by means of a hand wheel 51. On the other threaded. porti'o-n of said shaft and adjustable simul-- taneously with the block 50. is block 52. 5 The 'purposes'of said blocks 50 nd 52 will hereinafter be made apparent. A gear wheel 53 carried vby said shaft 48 meshes with a similar wheel 54 carriedby the shaft 49, said gear wheels serving toimpart to the last 123 mentioned shaft rotary movement'in a direction reverse to that given the shaft'48. Said shaft 49 is threaded in'a direction reverse to that of that portion of the shaft 48 on which theblock 50 is locatedand is also received 125..

by said block, as is most clearlyshown in Fig. 10; consequently, rotation of said shafts carries said block 50 forward-orbackward, according to the direction of rotation, and a forward .p'r. rearward. longitudinal' sliding slot 55 provided in the adjacent side of said casing-like guide 31. Pivotally mounted within the front end of that is, at the end which is mounted in the bracket 46-1's one end of altrigger 56 the opposite or free end of which is yieldingly maintained in an outwardly or laterally pressed position by means of a suitable spring, as 57. The said free end of said trigger, projected on beyond the corresponding end of the member 75, is of beveled hook or keeper form, as is clearly shown at 58 in' 66 carried by the rod Fig. 8, and normally has received in the keeper notch 58 thereof a lug 59 carried on the interior wall of the tubular portion 60 of a longitudinally movable contact member 60 to which leads a conductor 61 from the high potential side of the transformer. Said contact member has its said tubular portion movably mounted in the bearing bracket 47 and has interposed between the outer edge of said bracket and an annular rib or flange 6O formed thereon one 'or more coil springs 62 whereby, when it is released by said trigger, it is thrust outward into contact with a suitably' mounted contact member 63 to which leads the opposite terminal or conductor 64 thereof which faces the slot 55 the base of a' laterally extending dog 65 having a' forwardly directed bevel at its end adapted to be engaged and depressed by a pivoted arm 34 at the instant that the latter, actuated byithe rocker-arm 29, begins its forward stroke. Said dog 65 is projected outward through the side of the adjustable block 52 and is movable with the latter, its base being slidably seated against said trigger. The arm 66 is pivotally mounted in a recess 67 provided on the upper surface of the rod 34 and is normally held by a spring 68 in a position substantially at right angles to said rod. Thus, when said rod begins its forward movement, its free-end engages the bevel of'the dog 65 and causes,

from the lug 59, permitting the contact memcontact with contact member 63.

said member 75- ber 60, actuated by springs 62, to move into I Upon the return stroke of the rod 34, thearm 66 engages the dog 65 and is thereby swung forward against the tension of, spring 68 until 1t passes over said dog, when said arm resunies its normal position. Near the end of' the forward movement or stroke of the rod 34, a laterally projecting stud 69 carried by the adjustable block 50 is engaged by the arm 66, and, with the further movement of said rod, the said block 50 and the shafts 48 and 49 on which said block is mounted are together carried forward, said shafts having longitudinal sliding movement with respect to the bearing brackets 46 and 47.

-On the rear projecting end of theshaft 49 is a fixed head, or projecting peripheral flange, 70 between which and the adjacent face of the bracket 47 a strong spiral spring 71 is interposed, said spring serving to normally maintain said shaft 49 in a rearwardly thrust position. lVhen the contact member 60 lies in contact with contact member 63, as hereinbefore described, the outer face of the rib or flange 60 engages the inner face of the flange 70. Consequently, when the shafts 48 and 49 are carried forward, as hereinbefore described, the contact member 60 is retracted therewith against the tension of springs 62 to a point where the lug 59 is received in the keeper notch 58 of the hook 58 formed on the pivoted trigger 56, thus breaking the electric circuit through the transformeri The spring 71 acts to, return the shafts 48' and 49 to their'normal positions when the rod 34 starts back on its return stroke.

As is obvi0us,the blocks 50 and 52 are adjusted so that they are separated adistance substantially e ual to the length of the seam to be welded. This results in the welding circuit being closed at the beginning and broken at the end of the forward movement of the'wheel electrode.

As is obvious, suitable insulation must be provided at various points throughout the machine, as between the bracket 41 and the frame 10, as shown at 72, and between the guide 31 and its extension 31;, as shown at 73; however, since the parts to be insulated will be readily located by anyone skilled in vthe art, the insulation-has not been shown at all points where its use is required. 1

From the foregoing it will be noted that, when the rocker-arm 29 begins its forward stroke, actuating the rod 34 to move forward, the pivoted arm 66 immediately engages the beveled end of the dog 65 seated against trigger 56 andforces the latter inward as it passes over said end, thus releasing the spring-pressed contact member 60 which immediately assumes a position in contact with the stationary contact member contact member 60 then rests against the includes the horn electrode 39 and then moving wheel electrode 36. Just prior to reaching the end, of the forward strokeor movement of the rod 34:, the pivoted arm 66 carried thereby engages the stud 69 of the adjustable block 50, and, throughout the remainder of said stroke, actuates said block to travel forward, carrying therewith the shafts 48 and 494 Since the flange 60 of opposing fixed flange or head 70 of said rod 49, the said forward movement of the latter eflects the withdrawal of said contact member 60 from contact with contact-member 63, thus-breaking said transformer circuit.

What is claimed. is-

1; An electric welding machine comprising a horn electrode, a Wheel electrode mounted to travel along said horn electrode, a transformer having terminals connected to said electrodes, means for producing reciprocating movement ofsaid wheel electrode, and-means actuated by said movementproducing means for closing and opening the transformer circuit at predetermined points in the travel of said wheel electrode.

2. An electric welding machine comprising a horn electrode, a wheel electrode mounted to travel along said horn electrode, a transformer having terminals connected to said electrodes, rocking means for advancing and. retracting said wheel electrode, and means actuated by the first-mentioned means for opening and closing the transformer circuit at predetermined points in the ad Vance movement of said wheel electrode.

3. An electrlc weldmg' machine comprlsing a stationary horn electrode, a wheel electrode, "means yieldingly supporting said wheel electrode over said-horn electrode, a transformer having terminals connected to said electrodes, means for advancing and retracting said wheel supporting means, and automatically actuated means for opening and closing the transformer circuit at'predetermined points in the travel of said wheel electrode.

4. An electric welding machine comprising a stationary hornelectrode, a wheel electrode, means yieldingly supporting said wheel electrode over said horn electrode, a transformer having terminals connected to said electrodes, means for advancingland retracting said wheel supporting means, and means actuated by said; advancing and retracting means for opening and closing the transformer circuit at predetermined points in the travel of the wheel electrode.

' 5. An electric welding machinecomprising a horn electrode, a wheel electrode mounted to travel alon said horn electrode, 'a transformer having terminals connected to said electrodes, a pivoted rocker arm, means for rocking said arm back and forth, means interposed between said arm and said wheel electrode whereby reciprocating movement is imparted to the latter, and means actuated by the last mentioned means whereby the transformer circuit is in the travel of said wheel electrode.

GJAn electric welding machine comprising a horn electrode, a wheel electrode a transformer having terminals connected closed and opened at predetermined points ,mounted to travel along said horn electrode,

to said electrodes, a pivoted rocker-arm,

means forrocking said arm back and forth, means for adjusting the throw of sald arm, means interposed between .said arm and said ment of the former efiects reciprocating actuated .means closing 'and opening the in the travel of the wheel electrode.

7. An electric welding machine comprising a horn electrode, a Wheel electrode mounted to travel along said horn electrode, a transformer having terminals connected to said electrodes, a pivoted rocker-arm, means interposed between said arm and said wheel electrode whereby the rocking movement of the former fi'ects. reciprocating movement of the latter, a spring-pressed movable contact in the transformer circuit, means norwheel electrode whereby the rocking movetransformer circuit at predetermined points.

for rocking said arm back and forth, means for adjusting the throw of said arm, means movement of the latter, and automatically 7 mally maintaining said contact retracted in a position holding said circuit open, means for releasing said contact to close said cirof said w eel electrode, and means for returning said contact to retracted position at a predetermined point in said travel.

8. An electric welding machine comprising a horn electrode, a wheel electrode mounted to travel along said horn electrode, a transformer having terminals connected to said electrodes, a pivoted rocker-arm, means for rocking said arm back and forth, means ,for adjusting the throw of said arm, means interposed between said arm and said wheel elect-rode whereby the rocking movement of the former effects reciprocating movement of the latter, a spring-pressed movable contact in the transformer circuit, means normally maintaining said contact retracted in a position-hold 11g s'ai'd'circuit open, means for releasing said contact to close said circuit, at a predetermined point in the travel of said wheel electrode, means for returning said contact to retracted position at'a predetermined point in said travel, and means for adjusting the length of traverse of said Wheel electrode between the circuit closing and opening positions thereof.

9. An electric welding machine comprising a horn electrode, a wheel electrode cuit at a redetermined point in the travel. j

mounted to travel along said horn electrode, a transformer having terminals connected to said electrodes, a pivoted rocker-arm, means for producing a forward and return stroke 5 of said arm, means wherebylsaid movement is automatically stopped at the end of the return stroke, means interposed between said arm and said wheel electrode whereby a complete reciprocation of the latter is effected by said forward and return stroke, and means whereby the transformer circuit is closed and opened at predetermined points in said reciprocation. v,

10. An electric welding machine comprising a horn electrode, a wheel electrode mounted to travel along said horn electrode, a transformer having terminals connected to said electrodes, a ivoted rocker-arm, means for producing a orward and return stroke of said arm, means whereby sald movement is automatically stopped at the end of the return stroke, means interposed between said arm and said wheel electrode whereby a complete-reciprocation of the latter is ef- 2 5 fected by said forward and return stroke, and means whereby the transformer circuit is closed and opened at predetermined points in the forward stroke.

. 11. An electric welding machine comprising a horn electrode, a wheel electrode mounted to travel along said horn electrode, a transformer having terminals connected to said electrodes, a pivoted rocker-arm, a constantly rotating element, a normally stationary rotary shaft on which said element is mounted, means interposed between said shaft and said rocker-arm whereby rotation of the former oscillates the latter, a clutch interposed between said shaft-and said element, means normally maintaining said clutch disengaged from said element, means for withdrawing the last mentioned means, means actuating the released clutch to engage said element to operatively connect said shaft and said element, automatic means for disengaging said clutch from said element when said shaft has made a complete revolution, means interposed between said arm and said wheel electrode whereby oscillation of the former reciprocates the latter, and means 0 whereby the transformer circuit is closed. and opened at predetermined points in the .travel of said wheel electrode.

In testimony whereof, I- afiix my signaturein presence of two subscribing witnesses.

WILLIAM E. ANDREWS.

Witnesses:

H. E. DUNLAP,

, Roar. ELSON. 

